/* Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */


/**
  @file

  @brief
  Functions for discover of frm file from handler
*/

#include "sql_priv.h"
#include "unireg.h"
#include "discover.h"
#include <my_dir.h>

/**
  Read the contents of a .frm file.

  frmdata and len are set to 0 on error.

  @param name           path to table-file "db/name"
  @param frmdata        frm data
  @param len            length of the read frmdata

  @retval
    0	ok
  @retval
    1	Could not open file
  @retval
    2    Could not stat file
  @retval
    3    Could not allocate data for read.  Could not read file
*/

int readfrm(const char *name, uchar **frmdata, size_t *len)
{
    int    error;
    char	 index_file[FN_REFLEN];
    File	 file;
    size_t read_len;
    uchar *read_data;
    MY_STAT state;
    DBUG_ENTER("readfrm");
    DBUG_PRINT("enter", ("name: '%s'", name));
    *frmdata = NULL;     // In case of errors
    *len = 0;
    error = 1;

    if ((file = mysql_file_open(key_file_frm,
                                fn_format(index_file, name, "", reg_ext,
                                          MY_UNPACK_FILENAME | MY_APPEND_EXT),
                                O_RDONLY | O_SHARE,
                                MYF(0))) < 0)
        goto err_end;

    // Get length of file
    error = 2;

    if (mysql_file_fstat(file, &state, MYF(0)))
        goto err;

    read_len = state.st_size;
    // Read whole frm file
    error = 3;
    read_data = 0;                                // Nothing to free

    if (read_string(file, &read_data, read_len))
        goto err;

    // Setup return data
    *frmdata = (uchar *) read_data;
    *len = read_len;
    error = 0;
err:

    if (file > 0)
        (void) mysql_file_close(file, MYF(MY_WME));

err_end:		      /* Here when no file */
    DBUG_RETURN (error);
} /* readfrm */


/*
  Write the content of a frm data pointer
  to a frm file.

  @param name           path to table-file "db/name"
  @param frmdata        frm data
  @param len            length of the frmdata

  @retval
    0	ok
  @retval
    2    Could not write file
*/

int writefrm(const char *name, const uchar *frmdata, size_t len)
{
    File file;
    char	 index_file[FN_REFLEN];
    int error;
    DBUG_ENTER("writefrm");
    DBUG_PRINT("enter", ("name: '%s' len: %lu ", name, (ulong) len));
    error = 0;

    if ((file = mysql_file_create(key_file_frm,
                                  fn_format(index_file, name, "", reg_ext,
                                            MY_UNPACK_FILENAME | MY_APPEND_EXT),
                                  CREATE_MODE, O_RDWR | O_TRUNC,
                                  MYF(MY_WME))) >= 0) {
        if (mysql_file_write(file, frmdata, len, MYF(MY_WME | MY_NABP)))
            error = 2;

        (void) mysql_file_close(file, MYF(0));
    }

    DBUG_RETURN(error);
} /* writefrm */





